A drive circuit, as an important part of an LED application product, has gradually increased technical maturity with expansion of the LED market. A number of mature drive circuit products have emerged both in the field of lighting and backlight sources and in the field of display panels. Currently, most of these existing drive circuits need to be controlled by power management ICs. However, all the commonly used power management ICs generally have a complex structure and a high price, their application to the LED drive circuit will make the whole structure of the drive circuit complicated, and it is not conducive to reduction of the manufacturing cost of the drive circuit.